E85 gasoline?

Right back at ya.

All by itself it doesn't. But with increased octane, the engine management system should advance the timing to _USE_ the increased octane to produce more power. Dedicated E85 engines can have an increased compression ratio for more power.

That's why the engine management system should increase the volume of fuel each injector sends into the cylinder per firing as ethanol percentage increases.

Because your old fashioned carb engine cannot dynamically change engine timing and fuel metering nor can it detect changes in fuel composition.

A modern flex fuel vehicle should be able to do all of that. If a modern GM flex fuel vehicle had less power on E85 it's because GM screwed up or cheaped out on the engine management system.

I have been under the 'definite' impression that there is only so much compromise they can pull off and the end result is still poor performance and poor 'gas' mileage.

My engine just shows one extreme, an engine that 'only' uses ethanol would be the other extreme.

Mike

Poor performance is an issue only if the engine management system is not set up to make use of the ethanol. Having an engine management system that can sense and react to changes in fuel composition is what a flex fuel vehicle should have. Fuel economy as measured in distance per unit volume of fuel will always be dependent on energy per unit volume of fuel in some form or fashion.

Flex fuel and using ethanol are good things if properly implemented. The problem is that corn based ethanol using oil to produce it and perhaps some flex vehicles aren't that. The idea is to make ethanol without using oil and have flex fuel vehicles that take advantage of ethanol's properties.

I argued what a proper engine management system of a flex fuel vehicle should do.

That is what flex fuel vehicles have. They sense the increased alcohol content and increase timing and injector duration. The problem is that the lower compression ratio for the current gasoline does not allow for any power increase due to the lower energy available in the alcohol. Another problem being seen in flex fuel vehicles has been increased wear due to the washing effect of the alcohol in the cylinders.

I would almost think that a possible solution would be a variable compression ratio. Perhaps by using an additional chamber cast in the head and a solenoid valve. It could be opened to lower compression and closed to raise compression. Or another possibility could be a small turbocharger used to boost induction pressure when needed.

Ford apparently was able to get increased power some years ago. See super stallion.

If you're flooding cylinder walls with liquid fuel, gasoline or alcohol it's going to be bad. The only references I can find for increased cylinder wear on E85 is if the fuel is contaminated with water. Contaminated gasoline isn't good for a car either.

At least the water goes to the bottom of a gas tank. It mixes with alcohol....

My Jeep Cherokee's owners manual states to use 'no' alcohol of any kind mixes, no matter how many 'drying agents' they say they have in them. If in an emergency, only put enough in to get to 'real' gas.

Mike

Which is where the fuel pump pickup is.

That's what gas line antifreeze is for.... It is alcohol that mixes with the water in your tank so it can 'burn' away....

The problem is in the 'gas' station's tanks. They are allowed to have somewhere about 6" of water in the bottom of their tanks from condensation before their pickup starts getting it so the tank bottom has to be pumped out. They actually put some color changing gray past on the dipsticks to test for this every so often.

This water stays down there in a 'gas' tank. In an 'ethanol' tank, this condensation water mixes up and gets pumped into your tank which can rot any steel parts in the fuel supply system.

Mike

Not necessarily. The Ford 3.0L Flex Fuel engine actually had about 5% more power on E85 vs gasoline. Two factors at work here. One, the higher octane rating allows closer to optimal ignition timing (not necessarily more advance) and two, the significantly higher latent heat of vaporization improves volumetric efficiency.

Any volume produced flex fuel engine should pass the manufacturer's durability testing. This would include tests for abnormal bore wear.

Creating the problem that you are considering a fatal flaw of ethanol.

Flex fuel cars don't use carbon steel fuel system components, they use stainless.

The only way to eke out the extra potential is to raise the static compression ratio substantially... and if you do THAT, its no longer a "flex fuel" vehicle because it won't run on gasoline without detonating. You don't gain anything just by advancing the snot out of the timing on ethanol.

Ethanol is a non-starter as a fuel IMHO. Its "cool" now that there's a relatively small demand, but it will never replace gasoline. Vegetable oil may eventually replace DIESEL, I can see that happening. But not gasoline.

Nope. You get NO more power beyond a certain point when advancing timing. When you've advanced the timing to the point that peak pressure occurs before TDC, you actually start losing power again (and adding internal stress also).

Dedicated E85 engines can have an increased

Yep. No longer a "flex fuel" vehicle, but a true alky-burner.

Corn-based ethanol is really an inefficient means of fuel production. Brazil is heavy into sugar cane based ethanol production, which doesn't require anywhere near the energy output to produce, and probably doesn't need fertilizer. I've heard that sugar cane can practically be planted and left alone until ready for harvest.

Yet, some of the extra potential is gained with mere timing changes by the engine management system.... since the vehicles exist that do so I don't know how else to better prove it.

Ethanol is viable if made correctly. However the political process has been dominated by ADM's lobbists so that's probably not going to happen outside of HI.

That in no way invalidates what I stated above. Of course there is a limit it to it, but before that limit is reached power is increased.

Again, I point to the existing vehicles that do so. If I was wrong these vehicles wouldn't exist.

The idea is not use oil in the process and ideally have all the energy for the process come from the plants. While one part of the sugar cane plant produces ethanol another part of the plant is used to produce the energy for the process making it very good. Corn based ethanol can work if the energy for it's process comes from something vehicles can't use, like windpower. Ethanol can be a better 'battery' than any battery technology available to run vehicles on energy from wind, nuke, hydro, etc.

Of course Brazil razed an awful lot of rain-forest to turn into fields to gro sugar cane.... :-/

The systems that do that really just make it "less worse" to borrow one of Dan Stern's phrases.

I have yet to see any numbers that really prove that, although the South American sugar-cane based process where the stalks are used to fuel part of the distillation process is probably in the black energy-wise. I seriously doubt that its anywhere near a net gain pollution-wise, though, considering that a) I'll bet the stalks don't burn very cleanly and b) even if it is now "carbon neutral" the land used to produce the sugar cane was FORMERLY rain-forest, and a far more efficient carbon trap than sugar cane (not counting all the carbon released during the clearing of the rain-forest in the first place.)

How is more power 'less worse' than the power output you started with?

It's fairly logical, don't use oil to make it.

I didn't argue ethanol was better pollution wise. It's different, better is hard to say.

I'd like ethanol to succeed simply be another choice so that the schemes being used to keep gasoline and oil prices high would fail.